Effects of Mg-load on the contraction of uterus in sponteneously diabetic mice

镁负荷对自发性糖尿病小鼠子宫收缩的影响

基本信息

批准号：
08680050
负责人：
AOMINE Masahiro
金额：
$ 1.6万
依托单位：
Nakamura Gakuen University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08680050/
关键词：
Mg-load Diabetes mellitus Mouse Uterus Contraction Oxytocin

项目摘要

First, we investigated effects of external magnesium (Mg) on the contractile tension of uterus under the condition of Mg-unload, using spontaneously diabetic mice (KK/tA9 and the non-diabetic mice (c57/BL). Both KK/Ta and C57/BL mice were divided into the folloowing three groups : a group fed with normal diet (N-group) ; a group fed with normal diet, accompanied by pohysical exercice (whirl cage running)(T-group) ; a group fed with restricted diet (a half of normal volume), accompanied by the physical exercice (TD-group). External Mg decreased the amplitude and frequency of the contractile tension of uttlerus in a concentration dependent manner. IC_<50> of Mg in the amplitude and frequency of the tension in both mice was the smallest in N-group, followed by T-group and TD-group in the order. This tendency was more eminent in diabetic mice. Secondly, the inhibitive effects of external Mg on the contractile tension of utterus were studied, using Mg-load mice, and compared with Mg-unload mice. Mg-load was done by 1. p. injection of 2M MgCl_2 for 2 to 3 weeks. In Mg-load KK/Ta mice, serum Mg concentration was significantly higher than in Mg-load C57/Bl, whereas uterus Mg concentration was almost same in both mice. In Mg-unload mice, C57/BL uterus was more sensitive to external Mg than KK/Ta uterus. In Mg-load mice, however, the difference between KK/Ta and C57/BL disappeared, suggesting the relation between the contractility and the Mg concentration in the tissue. In oxytocin-induced contracture, Mg-load suppressed the amplitude of the contracture and significantly shortened the time to the peak contracture. These resyults strogly suggested that Mg may affect the affinity between oxytocin and the receptors, and the density of the receptors.

首先，我们使用自发性糖尿病小鼠（KK/tA9 和非糖尿病小鼠（c57/BL））研究了镁卸载条件下外部镁（Mg）对子宫收缩张力的影响。KK/Ta 和C57/BL小鼠分为以下三组：正常饮食喂养组（N组）；正常饮食喂养并伴有物理锻炼的组（旋转笼）跑步）（T组）；限制饮食（正常量的一半）并伴有体育锻炼的组（TD组）以浓度依赖性方式降低子宫收缩张力的幅度和频率。两种小鼠中Mg的张力幅度和频率的IC_<50>在N组中最小，其次是T组和TD组，这种趋势在糖尿病小鼠中更为突出。 , 抑制性使用镁负载小鼠研究外部镁对子宫收缩张力的影响，并与镁卸载小鼠进行比较。镁负载在 1 p 时完成。注射2M MgCl_2 2至3周。在镁负载 KK/Ta 小鼠中，血清镁浓度显着高于镁负载 C57/Bl 小鼠，而子宫镁浓度在两只小鼠中几乎相同。在镁卸载小鼠中，C57/BL 子宫比 KK/Ta 子宫对外部镁更敏感。然而，在镁负载小鼠中，KK/Ta 和 C57/BL 之间的差异消失，表明收缩性与组织中镁浓度之间的关系。在催产素引起的挛缩中，镁负荷抑制了挛缩的幅度并显着缩短了达到峰值挛缩的时间。这些结果有力地表明Mg可能影响催产素与受体的亲和力以及受体的密度。